A voltage pump is used to provide voltage to an external circuit. Voltage pumps have a single function, such as a read pump, a program/erase pump or a standby pump. The read pump provides a required voltage to the external circuit so that data can be read. A program/erase pump provides the required voltage to store or to erase data. A standby pump maintains a minimum voltage until other commands (e.g., program/erase, read) are received.